Rob Kardashian and Kylie Jenner Spotted Out Together for the First Time Since Blac Chyna Relationship Reveal

Despite the fact that Rob is dating Kylie's boyfriend Tyga's ex-girlfriend, the siblings appear to be in good spirits during their day out together today, which marked the first time we've seen these two spending time together since the news of his latest romance was revealed.

The 18-year-old was spotted picking her brother up from Blac Chyna's house Tuesday in her Rolls Royce so the two could head out for a meeting with Diamond Supply Co. founder Nicholas Tershay (aka Nick Diamond), which was conveniently documented on Snapchat, as all things are these days.

Kylie, dressed head to toe in black with her hair in the now-popular braids, was joined by her new puppy Odie, while her bro coordinated in black pants and a matching sweater with a black Los Angeles snapback. The duo flashed a smile for Diamond's Snapchat photo, and also said hello for a video clip that Tershay posted on the social media app, as well.

Tershay tweeted after the fact, writing, "Good meeting today with @robkardashian & @KylieJenner," but of course, no details about their conversation have been revealed.

You might recall that Rob recently visited the Diamond Supply Co. apparel store with Blac Chyna. The model posted a Snapchat video Friday showing the 28-year-old reality star inside a clothing shop appearing healthier and slimmer than he has for more than a year. He was standing in front of a mirror, wearing a gray hoodie and matching pants and Kanye West's Adidas Yeezy Boost 350 sneakers.

The pair were shopping for about an hour and seemed very happy together, a source told E! News exclusively at the time. Rob bought mostly gray blue hoodies, sweatpants and items from the Diamond Cordova collection, including crew neck tees. He also purchased clothes for Chyna, the source said.

Their retail therapy was shortly before leaving Los Angeles Saturday night and arriving in Montego Bay Sunday morning for a short trip in Jamaica because of Blac's hosting gig for the music festival Britjam.

She and Rob looked as happy as ever in photos and videos that have since surfaced on social media. In one photo Chyna cozies up to Rob, who has one arm wrapped around her. Wearing a black T-shirt and shorts, Rob has an ear-to-ear grin on his face as he holds onto his girlfriend.

"Things are very serious again and they are completely in love," a source told E! News, adding that Rob "is very thoughtful and giving."